A True Hero vs Divine Justice
by HaloGoji75
Summary: As the Underground is being ravaged by a god, only a hero with determination can hope to stand up to him


**Well, this is an idea that suddenly popped into my head, hope you all enjoy. Also, this takes place before a certain arc in Dragon Ball Super.**

* * *

The deity walked past the destruction he had wrought. The mortals of this world, the 'underground' as they called it, were almost wiped out. Any who dared stand against his divine justice were swiftly dealt with. He was one step closer to having his utopia realized. As he continued on his way, he saw a small figure standing in his path. He stopped and observed the creature before him. It was a small reptile like being that was an odd mix of yellow and brown. Small spikes ran down the back of his head. A jagged tail stuck out of its back. From what he could observe, it appeared to be a child. He knew about children all to well. They hid behind a veil of innocence, when in reality they were just as cruel as the adult mortals. The creature stood there, staring at him with trembling legs.

"S-stop." The creature said, quaking in fear. "If-if you want to go any further, you'll h-have to go through me."

He snorted in disgust. Another who stood in the way of utopia. He would be dealt with like the rest. Purple energy surrounded his right hand as he raised it. As he attempted to strike down the child, a second creature jumped in front of him. The blow slashed across it's chest, leaving a gaping wound.

"Undyne!" The child shouted in surprise.

"I'm fine." The new comer, known as Undyne, hissed out. "I'll hold him off, get the others to safety."

"But Undyne-"

"GO!"

The child hesitated for a moment, before he turned and ran towards the next settlement. It didn't matter. The child would eventually be vaporized with the rest of his kin. For now, he was more interested in the creature that stood before him.

It was female, that much he could tell. She was covered in a dull grey armor, reminiscent of a knight. Her face was blue and held qualities that resembled that of a aquatic life form. One yellow eye stared at him in hate, the other was covered in an eye patch. Yellow fangs filled her mouth, which was contorted in pain. She clutched her wounded chest, her knees trembling as she struggled to stand.

"H-h-how?" She asked, struggling to breathe. "With just a single blow, I'm in this state. How can a human be capable of this?"

His brow furrowed at that statement. During his quest, he learned that the people of this world despised humans as much as he did. But, that didn't exempt them from his justice, nor did it excuse them for referring to him as one.

"I am not a disgusting human." He replied. "I am a deity, and I am here to bring about justice."

"How is this justice?" Undyne wheezed out.

"I've seen what mortals have done to the universe. All the pollution, death, and destruction they are capable of." He said. "Mortal beings such as your self, are the Gods' greatest mistake, one which I intend to rectify."

Undyne gritted her teeth as she held out her free hand. A blue spear appeared in it for a brief moment, before fading away. She collapsed onto one knee as blood continued to leak out of her.

"D-damn." She hissed out.

"Still you attempt to defy divine justice." He said, malice in his voice. "You mortals brought this upon yourselves. You deserve this."

He walked pass her, content with letting her bleed to death. She deserved worse, they all did.

"No."

He paused as he heard her speak out. Even on the brink of death, she still defied him. Perhaps he should finish her off quickly. As he turned to face her, he was startled by the amount of power emanating off of her.

"I won't die, not yet." She said. "I refuse!"

She stood up on both her legs, body radiating with white light.

"If I do, then you'll kill them all." She said as she stared at him defiantly. "I won't let those who came before me die in vain. I'll avenge all of them."

Her body glowed brighter, causing him to shield his eyes.

"Son Goku." She said, referring to him by the name he at taken for himself. "For the sake of true justice, I, Undyne, shall strike you down where you stand!"

As the light faded, Goku gazed upon Undyne. Her armor had changed to a pitch black color. Spikes lined her shoulder guards. White gloves with black hearts on the wrist gripped two spears made of light tightly. Her eye patch disappeared, replaced by a glowing arrow that pulsated out of her eye. A heart as bright as her red hair was on her breast plate. She stared at him, determination evident on her features.

"HAVE AT YOU, FALSE GOD!" She screamed as she charged.

Goku barley had time to dodge before one of her spears impaled the ground where he stood. He readied his aura slide technique and attempted to strike her down, only for Undyne to block it. Caught off guard, Goku received a kick to the stomach, sending him into a nearby hill. Without delay, Undyne raced forward at speeds the naked eye could not track. She slashed at his left side and his face. Goku dodged the attempt on his head and kicked her away. As he was about to counter, he became aware of a wet feeling on his left. Placing a hand on his side, he felt a cold, thick liquid emanating from it. Raising it to his face, he observed his blood stained hand.

' _Blood?_ ' He thought to himself. ' _A mortal has drawn blood from me?_ ' Part of him was enraged, disgusted that a worthless life form such as this was able to injure him in such a manner. But the other part, the more dominant side, was thrilled. He started chuckling for a moment, before it became full blown laughter. Undyne stared at him, somewhat confused at this turn of events.

"Through out my quest, I have faced many mortals, none of whom have ever proven a match for me, until today." Goku said as he assumed a fighting stance, hands raised in front of him, legs spread apart. "Come Undyne, champion of the Underground, show me your power, so that I may test this body's limits."

Undyne regarded him for a moment, before summoning another spear and pointing it at him.

"If you insist Goku, destroyer of worlds." She replied.

The two fighters stared each other down for a moment, the smoke from the previous village Goku destroyed filled the sky. Then, they charged, blades of energy at the ready. Goku's ki covered hand clashed with Undyne's spear repeatedly. Undyne moved fast, striking lightning fast blows while Goku was more patient, blocking attacks and countering with a quick slash to her side. Both fighters exchanged blows at amazing speeds, their forms surrounded by blurs of purple and blue. Undyne screamed in rage as she continued her relentless assault, while Goku simply smiled. Finally, a worthy opponent. This body craved, no lusted, for combat. The more he fought, the stronger he would become. The stronger the opponent, the greater the thrill. He could already feel himself getting more powerful, his mind adapting to the body he had taken from the mortal he despised the most, and admired as much as he admired himself.

Undyne suddenly disappeared and reappeared behind Goku, slashing at his back. Goku then flew into the air and started raining ki blast down from the palm of his hand. Undyne deflected a few blast, but was hit by some stray shots, causing her to lose her balance. As she regained her footing, Goku flew in and landed a kick into her abdomen, knocking the wind out of her. Before he could react, Undyne grabbed Goku's leg and slammed him into the ground, a crate forming from the impact. Goku countered with a right hook to the face, knocking Undyne back. Undyne back flipped away before summoning several spears and throwing them at Goku. The god narrowly dodged the volley of projectiles, a few scratching his arms and legs, with one grazing his cheek. He never felt more alive. This, this is what he was missing.

"More, give me more!" He shouted. "Show me how powerful you really are, great warrior."

"Fine then," Undyne said, readying an attack. "How about this?"

Suddenly, Goku was surrounded by spears from all sides. They hovered in the air for a moment, before Undyne threw her hand forward, causing all of them to race towards their target. Goku moved quickly, dodging some, deflecting others, his smirk never once leaving his face. Then he shouted as he summoned his ki, an explosion of energy emanating from his body, causing all the spears around him to shatter. When the explosion faded, his body was surrounded by a dark aura. He hovered in the air, smirking, as he cupped his hands together while Undyne summoned more spears.

"Ka- me"

His hands went behind his back.

"Ha-me"

A dark ball of ki started shining in his hands as he prepared to use one of the greatest techniques of the one he despises the most.

Undyne's spears cluttered together before they formed one giant spear.

"HA!"

Goku's arms surged forward, releasing a beam of dark energy, just as Undyne threw her giant spear. The two attacks collided in mid air, pushing each other back. Goku continued to feed more energy into his blast while Undyne kept pushing

"This is for Papyrus, and everyone else you killed!" Undyne screamed as her spear doubled in size. "Taste the power of a true hero of justice!"

The large spear surged forward, cutting the Kamehameha in half. Goku barley had any time to react before the spear slammed into him. He screamed as he was slammed into the ground, causing the spear to explode. Smoke filled the air, obscuring Undyne's vision. When it cleared, she saw Goku lying in a crater, not moving.

"It's over." She gasped between tired breaths. "Papyrus, you can rest easy."

Before she could react, Goku suddenly surged out of the crater, his hand covered in ki. The blade of energy pierced her stomach and emerged out of her back. She coughed up blood as she stared at him in shock. Goku simply smirked as he pulled the blade out, letting Undyne collapse.

"Thank you Undyne." Goku said. "My power has grown even more because of this fight. You were a worthy opponent."

Undyne stared at him, blood leaking from her injuries, before she started laughing. Goku stared at her, curious about what was happening.

"You won, but it won't make a difference." Undyne wheezed out. "By now, the village has been evacuated. Now, you'll never find them."

"This is a minor setback at best." Goku replied. "They won't escape divine justice. But, as a thank you for providing me with a great challenge, I'll end their lives so quick, they wont feel a thing."

"You may be cocky now" Undyne gasped. "But, some day, someone will avenge all of us, and show you what justice really is. I thought I could do it, but that honor, belongs to someone else."

Undyne smirked at him in a mocking manner before finally collapsing, the life draining from her eyes.

Goku stared at the corpse of his most recent foe, paying some respect he rarely showed mortals, then he flew off to continue his quest.

* * *

Meanwhile...

Zamasu pulled the bone like spear out of his chest, fuming in rage. As his wound healed, he stared at the creature that offended him, who stared back with one, blue eye.

"Ready to have a bad time?"

* * *

 **Well, there you have it.**

 **"That, wasn't so bad. But why aren't you working in the Misadventures of Burn Squad?"**

 **I was, when this idea suddenly came to me. I felt compelled to write it. Now, for those of you wondering:**

 **1\. Yes, it is Goku Black. However, he referred to himself as Son Goku for a long time before Future Bulma called him Goku Black.**

 **2\. This takes place before the Future Trunks arc in Dragon Ball Super, Zamasu is still getting used to Goku's body. So, no Super Sayian Ros** **e.**

 **3\. If I portrayed any characters from Undertale incorrectly, I apologize. I don't really play Undertale, but I do watch a few videos about it every once in a while.**

 **So, with that out of the way, I hope you enjoyed. And if you want to do anything with this concept, feel free to do so.**


End file.
